This illustration compares the orbit of the binary Kuiper Belt object, called 1998 WW31, with the orbits of Pluto and Neptune, the outermost solar system planets. The inset picture, consisting of six snapshots taken by NASA's Hubble Space Telescope, shows one member of the Kuiper Belt pair [the faint white blobs] during its elliptical orbit. The bright white object at the bottom of the oval is the other member of the pair.